Atomic Structure and Periodic Table.

Question 1

What is Aufbau in German?

Answer 1

To fill up

Question 2

What is the Aufbau principle?

Answer 2

Lower energy sublevels must ve filled with electrons before higher levels can have electrons assigned to the.

Question 3

What is weird about 3d?

Answer 3

It doesn’t get filled until 4s is filled.

Question 4

When does 3d appear?

Answer 4

at n=4 (is always n-1).

Question 5

What is Hund’s Rule?

Answer 5

Every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied. Also, all electrons in singly occupied orbitals have the same spin.

Question 6

What is the Pauli Exclusion Principle?

Answer 6

AN orbital can hold 0, 1, or 2 electrons only. If there are 2 electrons in the orbital, they must have opposite spins. Therefore, no 2 electrons in the same atom can have the same set of four quantum numbers.

Question 7

What is electron configuration?

Answer 7

The shorthand representation indicating how many electrons are in the various orbitals.

Question 8

Which are the anomalies in electron configuration?

Answer 8

Mo, Ag, Au, Cr, Cu

Question 9

Why are there anomalies in electron configuration?

Answer 9

Because half-filled and comletely filled subshells represent conditions of preferred stability.

Question 10

What happens to the electron configuration of Cr?

Answer 10

AN electron shifts from the 4s into the 3d orbital to gain the extra stability of a half-filled 3d subshell.
[Ar]4s2, 3d4 becomes [Ar]4s1, 3d5

Question 11

What happens to the electron configuration of Cu?

Answer 11

AN electron shifts from the 4s into the 3d orbital to gain the extra stability of a filled 3d subshell.
[Ar]4s2, 3d9 becomes [Ar]4s1, 3d10

Question 12

How many electrons can be in the d orbital?

Answer 12

10

Question 13

For the electron configuration of anions, what must you do?

Answer 13

Add the extra electrons to the total number of electrons in the atom.Then distribute the electrons into the orbitals.

Question 14

For the electron configuration of cations, what must you do?

Answer 14

Write the electron configuration for the neutral atom first and the remove the required number of electrons from the highest principle quantum number (not necessarily the highest energy).

Question 15

In which order do you remove the electrons for the e config. of cations?

Answer 15

First in the outermost p orbital, then s, then d.

Question 16

What does isoelectronic mean?

Answer 16

Having the same electron configuration.

Question 17

What are Cl- and S2- both isoelectronic with?

Answer 17

Ar.